I do development on multiple computers, and on OSX as Well as Windows. Is there any way to put my databases in my Dropbox folder, and allow Dropbox to keep the files on each computer up to date so that I don't have to manually recreate my databases on each computer I work on?

If you relocate your databases then you would need to change the settings in the \xampp\mysql\bin\my.ini file under the section [mysqld] item datadir="" so the server knows where to look for them.There is also a reference to the datadir under the innodb section which also may be required to be taken into account.